A Hawaii state auditor says a proposal to regulate zip line tour companies would cost $400,000 to set up and $350,000 to implement each year, with unclear benefits to making rides safer.

State Auditor Marion Higa said in a report submitted to Gov. Neil Abercrombie and the Hawaii Legislature that there’s not enough evidence to suggest zip lines are seriously dangerous, despite the death of a worker testing a new zip line on the Big Island last year.

Higa says the industry has a generally good safety record given that zip lining and similar activities are inherently risky.

State lawmakers introduced a bill in January to have 22 zip line companies regulated by the Department of Labor and Industrial Relations. It was referred to the House Finance Committee in March.